ANSYS APDL Solid45 KEYOPT(1) = 0, What is the logical meaning of Include extra displacement shapes?

[hogeol]

Q. What is the logical meaning of “Include extra displacement shapes(KEYOPT(1)= 0)“?
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Hello everyone.

I just knew the difference[1] between 'KEYOPT(1)= 0' and 'KEYOPT(1)= 1'.
By solving example problem[2], I can understand that there is difference.

My question: What is the logical meaning of “Include extra displacement shapes(KEYOPT(1)= 0)“?

From [3], the meaning is written as “add extra degrees of freedom”.
Then I don’t know the difference between other SOLID type such as SOLID95(20nodes).

Thanks you all.
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[1]
I look into ANSYS HELP. It is written as following:
“KEYOPT(1):
Include or suppress extra displacement shapes:
0 -- Include extra displacement shapes,
1 -- Suppress extra displacement shapes”

[2]
When the force is applied at mid span,
the responses at same location are
a) KEYOPT(1)= 0 : -0.15629E-01
b) KEYOPT(1)= 1 : -0.13081E-01

When properties and boundary conditions are as follows:
- Properties
L = 4; b = 0.08; h = 0.04;
E = 2*1E11; nu = 0.29; rho = 8000;

nnn = 2; Le = 0.04/nnn;

- Boundary Conditions
nsel, s, loc, x, L-Le/10,L+Le/10
nsel, r, loc, y, h/2-Le/10,h/2+Le/10
d,all,uy
d,all,uz

nsel,s,loc,x,0-Le/10,0+Le/10
nsel,r,loc,y,h/2-Le/10,h/2+Le/10
d,all,ux
d,all,uy
d,all,uz

[3]

http://www.eureka.im/3225.html

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